As it is known in the art, a Wireless Local Area Network (WLAN) is a local-area network that uses high-frequency radio waves or infrared links to communicate over an air link between coupled client devices. Because signaling is performed over an air link, the radio signals may be accessible to anyone capable of monitoring the air link, and thus there may be concerns regarding the privacy of data carried by a WLAN.
A variety of wireless communication environments exist. For example, an enterprise network may include hardware that permits each of the employees at a given corporate locale to communicate wirelessly with each other and a secured Local Area Network (LAN). In addition, WLAN use within homes is increasing, as vendors are providing more and more devices (such as television, stereos, etc.) which include WLAN communication functionality. With such an arrangement, a user connected to the home WLAN may control via one client device (for example a personal computer) the operation of any of the other coupled client devices.
In order to secure data that is exchanged between client devices in a WLAN network, various symmetric key encryption schemes have been defined and are continuing to be defined by standards bodies such as the IEEE to protect WLANs (this includes Wireless Equivalent Privacy (WEP), Temporal Key Integrity Protocol (TKIP), and Advanced Encryption Standard (AES)). It is generally recognized that symmetric key schemes will continue to evolve as the technology advances.
For example, WEP is designed to provide the same level of security to a WLAN network as that in a wired LAN. LANs are inherently more secure than WLANs because LANs are somewhat protected by the physicality's of their structure, having some or all of the network inside a building that can be protected from unauthorized access. Because communication in WLANs occurs over radio waves, WLANs do not have the same physical structure and therefore are more vulnerable to tampering. WEP aims to provide security by encrypting data over radio waves so that it is protected as it is transmitted from one end point to another.
According to the WEP protocol, when a client device is initialized into a WLAN network, it establishes communication with a router or a network Access Point (AP) and selects a WEP key. A user at the client device also copies the same WEP key into their client device. Further communications between the router/AP and the client device are then secured using the WEP key according to the WEP protocol.
Although the WEP protocol provides a mechanism for securing communication between clients in a WLAN, in use it can be cumbersome to the average user who knows little about proper key selection and the advantages of encryption. In addition, even if the user is capable of entering an appropriate WEP key, the process of WEP key initialization presents numerous opportunities for the key to be retrieved by a bad-faith client monitoring the air links. Thus, it is relatively easy for the security of the WLAN network to be compromised. It would be desirable to identify a straightforward method and apparatus for securing communication in a WLAN network which could be applied to any symmetric key encryption system.